From: drh <drh@noemail.net>
Date: Mon, 9 Feb 2009 17:34:07 +0000 (+0000)
Subject: Add assert() statements to os_unix.c which fire if there is a read or
X-Git-Tag: version-3.6.15~480
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=08c6d4468c2734ff44142f6c13461db49f529b4b;p=thirdparty%2Fsqlite.git

Add assert() statements to os_unix.c which fire if there is a read or
write for the locking region of a database file. (CVS 6270)

FossilOrigin-Name: 93e792ffa88ba2e8422d041f36b70d9b2e220da2
---

diff --git a/manifest b/manifest
index 8d6591cfb4..a2b8e3a1f8 100644
--- a/manifest
+++ b/manifest
@@ -1,5 +1,5 @@
-C Better\serror\smessage\swhen\sDISTINCT\sis\sused\son\san\saggregate\sfunction\sthat\ntakes\stwo\sor\smore\sarguments.\s\sTicket\s#3641.\s(CVS\s6269)
-D 2009-02-09T13:19:28
+C Add\sassert()\sstatements\sto\sos_unix.c\swhich\sfire\sif\sthere\sis\sa\sread\sor\nwrite\sfor\sthe\slocking\sregion\sof\sa\sdatabase\sfile.\s(CVS\s6270)
+D 2009-02-09T17:34:07
 F Makefile.arm-wince-mingw32ce-gcc fcd5e9cd67fe88836360bb4f9ef4cb7f8e2fb5a0
 F Makefile.in c7a5a30fb6852bd7839b1024e1661da8549878ee
 F Makefile.linux-gcc d53183f4aa6a9192d249731c90dbdffbd2c68654
@@ -141,7 +141,7 @@ F src/os.c ed93a6b46132a602c4fd7a58142e2981c829c79d
 F src/os.h fa3f4aa0119ff721a2da4b47ffd74406ac864c05
 F src/os_common.h 24525d8b7bce66c374dfc1810a6c9043f3359b60
 F src/os_os2.c bed77dc26e3a95ce4a204936b9a1ca6fe612fcc5
-F src/os_unix.c 9f89f98c0782b89a73af08b8acc8bb5d3de5883d
+F src/os_unix.c 4e916cafbf5ec0166213ac62d680ebbe12b8c5a7
 F src/os_win.c 45cb430884da7e9360a55a0fcd5c2c44c22dd79d
 F src/pager.c 8c946cca1c1e64bd2d4b15aa431481c96233c826
 F src/pager.h 0c9f3520c00d8a3b8e792ca56c9a11b6b02b4b0f
@@ -701,7 +701,7 @@ F tool/speedtest16.c c8a9c793df96db7e4933f0852abb7a03d48f2e81
 F tool/speedtest2.tcl ee2149167303ba8e95af97873c575c3e0fab58ff
 F tool/speedtest8.c 2902c46588c40b55661e471d7a86e4dd71a18224
 F tool/speedtest8inst1.c 293327bc76823f473684d589a8160bde1f52c14e
-P 8227af3463ded1c52d0a16c63b8dbc516eab57f0
-R 9a4d5504a51006e95998fd3982eea1ce
+P e20bf384668bcde7c2f2152ca88e28cf65a02679
+R 3a3cb4e439892d819d6a33e750f5e099
 U drh
-Z 1fde4cf0408e6164f6078718fa7ec068
+Z 7b54fb55986a7fded747f515afad0223
diff --git a/manifest.uuid b/manifest.uuid
index f258911999..210287e1c1 100644
--- a/manifest.uuid
+++ b/manifest.uuid
@@ -1 +1 @@
-e20bf384668bcde7c2f2152ca88e28cf65a02679
\ No newline at end of file
+93e792ffa88ba2e8422d041f36b70d9b2e220da2
\ No newline at end of file
diff --git a/src/os_unix.c b/src/os_unix.c
index dd746e6db6..5696b141c6 100644
--- a/src/os_unix.c
+++ b/src/os_unix.c
@@ -43,7 +43,7 @@
 **   *  Definitions of sqlite3_vfs objects for all locking methods
 **      plus implementations of sqlite3_os_init() and sqlite3_os_end().
 **
-** $Id: os_unix.c,v 1.240 2009/02/09 05:32:32 danielk1977 Exp $
+** $Id: os_unix.c,v 1.241 2009/02/09 17:34:07 drh Exp $
 */
 #include "sqliteInt.h"
 #if SQLITE_OS_UNIX              /* This file is used on unix only */
@@ -183,7 +183,9 @@ struct unixFile {
   unsigned char locktype;          /* The type of lock held on this fd */
   int lastErrno;                   /* The unix errno from the last I/O error */
   void *lockingContext;            /* Locking style specific state */
-  int openFlags;                   /* The flags specified at open */
+#if SQLITE_ENABLE_LOCKING_STYLE
+  int openFlags;                   /* The flags specified at open() */
+#endif
 #if SQLITE_THREADSAFE && defined(__linux__)
   pthread_t tid;                   /* The thread that "owns" this unixFile */
 #endif
@@ -202,6 +204,11 @@ struct unixFile {
   unsigned char transCntrChng;   /* True if the transaction counter changed */
   unsigned char dbUpdate;        /* True if any part of database file changed */
   unsigned char inNormalWrite;   /* True if in a normal write operation */
+
+  /* If true, that means we are dealing with a database file that has
+  ** a range of locking bytes from PENDING_BYTE through PENDING_BYTE+511
+  ** which should never be read or written.  Asserts() will verify this */
+  unsigned char isLockable;      /* True if file might be locked */
 #endif
 #ifdef SQLITE_TEST
   /* In test mode, increase the size of this structure a bit so that 
@@ -2689,6 +2696,12 @@ static int unixRead(
 ){
   int got;
   assert( id );
+
+  /* Never read or write any of the bytes in the locking range */
+  assert( ((unixFile*)id)->isLockable==0
+          || offset>=PENDING_BYTE+512
+          || offset+amt<=PENDING_BYTE );
+
   got = seekAndRead((unixFile*)id, offset, pBuf, amt);
   if( got==amt ){
     return SQLITE_OK;
@@ -2754,6 +2767,11 @@ static int unixWrite(
   assert( id );
   assert( amt>0 );
 
+  /* Never read or write any of the bytes in the locking range */
+  assert( ((unixFile*)id)->isLockable==0
+          || offset>=PENDING_BYTE+512
+          || offset+amt<=PENDING_BYTE );
+
 #ifndef NDEBUG
   /* If we are doing a normal write to a database file (as opposed to
   ** doing a hot-journal rollback or a write to some file other than a
@@ -3678,6 +3696,12 @@ static int unixOpen(
     *pOutFlags = flags;
   }
 
+#ifndef NDEBUG
+  if( (flags & SQLITE_OPEN_MAIN_DB)!=0 ){
+    ((unixFile*)pFile)->isLockable = 1;
+  }
+#endif
+
   assert(fd!=0);
   if( isOpenDirectory ){
     rc = openDirectory(zPath, &dirfd);